There is no way these things could spread poison instead of pollen is there?

There is no such thing as ‘free speech friendly’. Free speech is not absolute, and is defined / restricted differently across countries. So different instances will have to comply with their different local laws.

Also: an instance allowing comments doesn’t mean there won’t be consequences. For example: you can criticise the Thai royal family all you want on a US based instance, but don’t ever show your face in Thailand after doing that if you value your freedom.